Twifficiency, in a nut shell, calculates your twitter efficiency based upon your twitter activity. This includes how many people you follow, how many people follow you, how often you tweet and how many tweets you read. "Earlier, it just automatically tweets out your results, now the team has changed the code, if you don't want to post your Twifficiency just untick the "check box" next to "Post my results to Twitter":
It all began, When Google's Marissa Mayer tried Twifficiency, and got tweeted out her total failure of the exam to her 35,000 followers. "My Twifficiency score is 0%. What's yours?," Mayer tweeted.
Mayer quickly followed up with a tweet: Lesson learned! RT @adamrofer my twifficiency is "I don't trust them to tweet on my behalf"